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111.
《International journal of human-computer studies》2013,71(6):691-702
This paper describes MTi, a biometric method for user identification on multitouch displays. The method is based on features obtained only from the coordinates of the 5 touchpoints of one of the user's hands. This makes MTi applicable to all multitouch displays large enough to accommodate a human hand and detect 5 or more touchpoints without requiring additional hardware and regardless of the display's underlying sensing technology. MTi only requests that the user places his hand on the display with the fingers comfortably stretched apart. A dataset of 34 users was created on which our method reported 94.69% identification accuracy. The method's scalability was tested on a subset of the Bosphorus hand database (100 users, 94.33% identification accuracy) and a usability study was performed. 相似文献
112.
113.
Dimas?Martínez?MoreraEmail author Paulo?Cezar?Carvalho Luiz?Velho 《The Visual computer》2008,24(12):1025-1037
This paper discusses the problem of modeling on triangulated surfaces with geodesic curves. In the first part of the paper
we define a new class of curves, called geodesic Bézier curves, that are suitable for modeling on manifold triangulations. As a natural generalization of Bézier curves, the new curves
are as smooth as possible. In the second part we discuss the construction of C
0 and C
1 piecewise Bézier splines. We also describe how to perform editing operations, such as trimming, using these curves. Special
care is taken to achieve interactive rates for modeling tasks. The third part is devoted to the definition and study of convex
sets on triangulated surfaces. We derive the convex hull property of geodesic Bézier curves.
相似文献
Luiz VelhoEmail: |
114.
在保证弧齿锥齿轮加工过程中刀盘相对于工件的运动关系不变的基础上,通过矩阵变换实现铣齿加工的数控展成.由于在数控加工每个插补周期中难以实现这种涉及大量运算的运动转换,因此将数控坐标轴的展成运动表示为以工件齿轮转角为参数的五次参数样条函数,保证了插补的实时性和精确性.文中将传统用于确定接触点位置时求解非线性方程组的问题,转化为带有3个设计变量的约束优化问题,简化了法线重合的条件,建立配对齿轮位置矢量相等的目标函数.最后给出实例对算法进行了说明和验证. 相似文献
115.
Daniel Cohen-Or 《计算机科学技术学报》2009,24(1):1-5
In recent years we have witnessed a large interest in surface deformation techniques. This has been a reaction that can be
attributed to the ability to develop techniques which are detail-preserving. Space deformation techniques, on the other hand,
received less attention, but nevertheless they have many advantages over surface-based techniques. This paper explores the
potential of these two approaches to deformation and discusses the opportunities that the fusion of the two may lead to.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
116.
117.
李绍霞 《数码设计:surface》2009,(8):295-297
点、线、面元素是艺术设计最基本的元素,在云南民族包设计中普遍运用。本论文主要从点、线、面的性质和作用来阐述了点线面元素是如何在云南民族包设计中得到运用的,从而使民族包的语言得到了充分的发挥。 相似文献
118.
Jong Sung Yoon 《Computer aided design》2008,40(9):905-915
This paper presents a simple and efficient method to approximate a developable surface to a compound design surface by a polynomial. It is required to predict a final shape of roll bending in the fabrication of a curved shell plate. The roll bending process usually makes the cylindrical or conical curvature from an initial flat plate. It means that the final shape is developable or the surface representation has zero Gaussian curvature. The fabrication shape is important in order to estimate process parameters of roller bending.An optimization problem is formulated to determine the polynomial surface which is in the closest proximity to the design surface or the given shell plate, which is subjected to developability. The results and the efficiency of this algorithm are verified and evaluated by applying it to some shell plates which are obtained from a real ship model. The predicted bending shape becomes fundamental information in determining more process parameters for the fabrication of a compound curved shell plate. 相似文献
119.
120.
S. A. R. Scrivener S. M. Clark N. Keen 《Computer Supported Cooperative Work (CSCW)》1994,2(3):137-157
This paper describes a shared workspace system known as the LookingGlass. The system allows pairs of geographically distributed designers to work together in real-time via a computer-based shared drawing surface, a video link and an audio link. The system integrates many of the features found in previous shared drawing surface systems and additionally provides eye-to-eye contact between the users; awareness of onea's partner's direction of gaze in relation to oneself and the worksurface; and the ability to communicate using gestures in relation to the worksurface.These features are achieved in the LookingGlass system using a technique referred to as video-overlay which combines a full screen video image of a remote partner with a full screen shared drawing surface. Various configurations of video-overlay have been explored and the results of these studies are presented. The results of trials into the suitability of the LookingGlass for various types of design work are also presented and described. 相似文献